Sewing machine



March 30, 1937. D c MQRELAND 2,075,537 Q SEWING MACHINE 2 Shets-Sheet 1Filed Jar 1. 8, 1935 i J JJMKW/ZZ March 30, 1937. D. c. MORELAND2,075,537

SEWING MACHINE Filed Jan. 8, 1955 2 Sheets-Sheet 2 A. 0 4% in, I/

Patented Mar. 30, 1937 UNITED STATES PATENT OFFIE SEWING MACHINEApplication January 8, 1935, Serial No. 867

2 Claims.

This invention relates to sewing machines, and while in some aspects notlimited thereto, is of special utility in connection with machines forsewing on buttons or the like.

5 The Lyons Patent No. 1,915,831 granted June 27, 1933, discloses amachine for sewing on buttons in which provision is made, for a purposefully set forth in that patent, to pull back the cast off loops ofthreads in two stages with an '10 intermediate dwell. One of the objectsof the present invention is to provide a simplified mechanism foraccomplishing the same result and which eliminates certain threadingoperations required by the patented construction.

The construction of the present invention also provides for easyadjustment of the amount of pull back in the initial pulling operationand the duration of the dwell.

For a more complete understanding of this invention, reference may behad to the accompanying drawings in which Figure 1 is a side elevationof a two-needle button sewing machine constructed in accordance withthis invention.

Figure 2 is a front elevation of the sewing head showing the needlesfully retracted.

Figures 3 to 6 inclusive are somewhat diagrammatic views showingsuccessive positions of the needle bar and needle and correspondingpositions of the looper mechanism.

Referring first to Figure 1, at l is indicated a suitable support, suchas a table top, on which is pivoted as on the cotter pins 2, a sewingmachine base 3. This base 3 is provided with spaced lugs 4 whichcooperate with lugs 5 secured to the upper face of the support I andreceive therethrough the pivot cotter pins 2. The machine base 3 isprovided with the usual upstanding sewing arm i at one end which extendsover the base toward the front of the machine and has on its forward endthe sewing head 8. The sewing head has reciprocably mounted therein aneedle bar 9 which may be reciprocated by any suitable means such as thecrank l carried by a rotary shaft II, the crank being connected througha link I 2 to an element 13 secured to the needle bar. The shaft llextends through the sewing arm in the usual manner and is shown asconnected through a crank l and a connecting rod IS with a crank I! on amain drive shaft I8 mounted in the base 3. The shaft 18 is provided witha cam l9- at its forward end having suitable cam paths such as 20 and 2|for control of the various thread handling mechanisms, such as the usualthread finger which cooperates with suitable loop takers such as 22. Asshown there are two of these loop takers in the form of oscillatoryloopers which may be driven from the main drive shaft i8 as shown in theLyons Patent No. 1,915,831 in suitable timed relation to the strokes ofthe needle bar 9. Cooperating with these loop takers are the two needles25, both of which are secured to the lower end of the needle bar 9. Thevarious sewing instrumentalities and work handling devices cooperatingtherewith may be identical with those shown in this Lyons patent.

To the top of the sewing arm 1 is seemed a bar 39 which extends over apair of thread stands 28, one on each side of the arm 1 and has thethread guide openings therein from which the threads from the stands areled and from which both are passed to the automatic tension 35, which isactuated at suitable times in the cycle of operation to grasp or releasethe thread in the manner disclosed in the Lyons patent. From the tension35 both threads are led through a thread guide 36, and thence to apermanent ten sion 31. After passing this tension 37 they are directedthrough a thread guide at 38 and then through thread guide holes 39through the needle bar 9 in a portion thereof extending above the sewinghead 8. From this needle bar they pass down over the front face of thesewing head to the tension 40 and from this tension 43 they pass to theeyes of the needles 25.

Between the tension 40 and the needle bar thread guides 39 andadjustably secured to the front face of the head 8 is positioned amember 42 with which the threads may engage at suitable times in thestitching cycle for a purpose which will later be described. As shown inFigures 2 to 6, this member 42 consists of a bar portion 43, which asbest shown in Figure 1, has a rounded top face 44, this bar having ashank portion 45 which may engage in a shallow channel 46 in the frontface of the head 8 and be adjustably secured therein as by a screw 41passing through a slot 48 in the shank portion and threaded into theforward face of the head 8. The member 42 is so adjusted that as theneedle bar 9 approaches the limit of its downward or sewing stroke, asshown in dotted lines in Figure 1, the thread guides 39 are broughtbelow the upper face of the bar portion '43, increasing the length ofthe path through which the thread passes from the bar guides 39 to thethread tension 40 and thus to the needles 25. Also the needle bar threadguides 39 when approaching the limit of the down motion of the needlebar pass beyond a straight line between the guide portion 38, where thethread emerges, and the top 44 of the bar portion 43, thus to lengthenthe thread path between the guide 38 and the bar 43 as shown in dottedlines in Figure 1.

These two actions result in the thread being pulled back through thetension 48, which is looser than the tension 37, as the needleapproaches its lower limit of sewing stroke, this pull back beingsucceeded by a dwell as the needle bar starts to retract and until theguides 39' are as much above the straight line position between theguide 38 and the top of the bar 43 as they were previously below thisstraight line position on the downward or sewing stroke of the needle.Further upward motion of the needle bar 9 then continues the drawingback of the thread until the needle bar reaches its highest positionshown in Figures 1 and 5.

Referring to Figures 3 to 6, it will be noted that when the needle baris descending so that the thread just begins to bear over the bar member43, the needles 25, one of which only is shown in these figures becausethe two needles are in front to rear alinement, are near the lower endsof their strokes and the hook at of each looper projects through theloop of thread previously taken down by its needle and which has beenopened for the passage of the needle by the action of the thread finger5i. As the needle bar descends further toward the position of Figure 4,the looper hooks 50 retract, casting ofi" the previously opened loopsonto the needles and over the loops of thread then in the needle eyes,the cast off loops being then drawn loosely back around the needles, butout of the way of the looper hooks, so that on their next forwardpassage, as shown in Figure 6, to take the succeeding loops from theneedles, they do not engage the cast ofi loops.

On the further retraction of the needle bar to its full retractedposition shown in Figure 5, the cast off loops are pulled up tightagainst the work, leaving the loops just taken from the needles on thelooper hooks 5i) ready for a succeeding down stroke of the needles tothe position shown in Figure 3. It will be noted that the use of themember 42 does not require any additional threading of the threadsbetween the needle bar and the tension 40 and that by verticaladjustment of the member 42, the amount of the initial pull back of thethreads to escape the hooks and to partly tighten the cast off loopsabout the needles may be adjusted to suit the particular conditions atany time. For the greater portion of the stroke of the needle bar, thethreads bear very lightly on the member 42 so that it does not produceappreciable wear thereon, nor is it itself subject to rapid wear fromthe threads passing thereover.

From the foregoing description of an embodiment of this invention, itshould be evident to those skilled in the art that various changes andmodifications might be made without departing from the spirit or scopeof this invention as defined by the appended claims.

I claim:

1. In combination in a sewing machine, an arm, a sewing head at theforward end of said arm, a needle bar reciprocable in said head, aneedle carried by said bar, a thread guide on said bar, a thread tensionon said head between said bar guide and said needle, and a member withwhich the thread may engage carried by said head between said tensionand bar guide and acting on the last portion of the sewing stroke ofsaid needle to effect an increased length of thread path between saidtension and bar guide.

2. In combination in a sewing machine, an arm, a sewing head at theforward end of said arm, a needle bar reciprocable in said head, aneedle carried by said bar, a thread guide on said bar, a thread tensionon said head between said bar guide and said needle, a member with whichthe thread may engage carried by said head between said tension and barguide and acting on the last portion of the sewing stroke of said needleto effect an increased length of thread path between said tension andbar guide, and means facilitating adjustment of the position of saidmember to thereby determine the amount of such increase.

DANIEL C. MORELAND.

